Base64
Encode or decode Base64 text.
Frequently asked questions
What is Base64 encoding?
Base64 represents binary data using 64 printable ASCII characters, so it can travel safely through systems that only handle text — for example email attachments and data URLs.
Is Base64 encryption?
No. Base64 is reversible encoding, not encryption. Anyone can decode it. Never use it to protect secrets.
Does my text leave the browser?
The conversion runs on our server over HTTPS and nothing is stored, but for sensitive data prefer an offline tool.
What is the difference between Base64 and Base64URL?
Standard Base64 uses the plus and slash characters and equals padding, which are unsafe in URLs. Base64URL replaces plus and slash with dash and underscore and often drops padding, so the result is safe in links and JWTs.
Why does Base64 output end in one or two equals signs?
The equals signs are padding that makes the output length a multiple of four when the input byte count is not divisible by three. They carry no data and simply signal how many bytes the final group represents.
How much larger does Base64 make my data?
Base64 grows the data by about a third, since every three bytes become four characters. That overhead is the trade-off for turning binary safely into plain text.
Can I Base64-encode any file, not just text?
Yes. Base64 works on the raw bytes of any data, including images, PDFs and binaries, which is why it is used for email attachments and data URIs.